Over the last decade, “electronic sensing” technologies have undergone important developments from a technical and commercial point of view. The expression “electronic sensing” refers to the capability of reproducing human senses using sensor arrays and pattern recognition systems. Since 1982 research has been conducted to develop technologies, commonly referred to as electronic noses that could detect and recognize odors and flavors. These devices have undergone much development and are now used to fulfill industrial needs.
Electronic nose instruments are used by research and development laboratories, quality assurance (QA), quality control (QC) laboratories and process & production departments for various purposes: Many devices for detecting odors exist, all of which take into account the specific chemical composition of the volatile components of the sample a scent.
Some examples of devices known from the patent literature are briefly described below.
US Patent Publication No. 2012/0143804, the disclosure of which is incorporated here by reference, describes an apparatus for assessing odors by an electric nose, to be applied to an odor and to output a structure identifying the odor; a neural network which maps an extracted structure to a first location on a pre-learned axis of odor pleasantness; and an output for outputting an assessment of an applied odor based on said first location. The assessment may be a prediction of how pleasant a user will consider the odor.
U.S. Pat. No. 8,272,280 presents a method and apparatus for detecting contaminants in the food industry by collecting air samples by containing aerosolized contaminate particles from a foodstuff and analyzing the sample for presence of a contaminate. Aerosol lab-on-a-chip and/or electronic nose devices are utilized for the detection of contaminant particles.
U.S. Pat. No. 7,593,863 describes systems and methods for measuring and testing a product using artificial olfactometry and analytical data sensory to identify preferences, which accurately facilitates a consumer's choice between products using descriptors of similar yet different products. The systems and methods provide an objective recommendation based upon analytical descriptors and attributes of particular products, and eliminate the subjective recommendations of persons familiar with many comparable and related products and thereby makes objective recommendations between products.
U.S. Pat. No. 7,167,815 suggests quantifying the intensity of an odour by determining what is the response of an odour sensing device to that odour, then transforming the response data to an odour intensity value based on transformation data relating to a set of selected reference odours. The transformation data includes organoleptic data indicating how odour intensity values assigned to the set of reference odours by a sensory panel depend upon the concentration of the reference compounds and includes data indicating how the response data of the odour sensing device when exposed to the set of reference odours depends upon the concentration of the reference compounds. The reference odours may be basic odours defining the dimensions of a multi-dimensional space in which odours can be defined.
U.S. Pat. No. 5,627,307 describes an odor intensity index measuring apparatus for measuring odor intensity objectively and easily for various types of odor. Sample air is diluted with odorless air at a desired scale factor in a dilution unit. The diluted air is fed through an air duct to an odorometer. Corresponding to the intensity of odor, voltage V is emitted from the odorometer. In an electronic control unit, the scale factor at which sample air is diluted by the dilution unit is gradually increased. The dilution scale factor which is reached when the output voltage from the odorometer becomes lower than the specified value indicating the odorless condition is displayed on a liquid crystal display. Like the conventional three bag odor comparison method, the odor intensity index can be measured in the same manner for various types of odor. Different from the conventional method, the degree of the odor intensity can be measured objectively without relying on the human sense of smell.
U.S. Pat. No. 7,734,436 describes comparative analysis of a sample, derived from a product, with respect to a database by determining the class membership of the different characteristics (variables) describing the samples: are they characteristics common to the sample under test and the database, are they characteristics particular to the sample under test, or are they characteristics particular to the database? The assignment of the variables to these classes enables parameters to be defined for global comparison of the sample under test and the database, based on: ratios summarizing the values taken by the variables of the different classes, or the distribution of the variables of the different classes.